I have several things to say.
First: Welcome! <img src="i/expressions/face-icon-small-smile.gif" border="0">
Second: This isn't the best place for you to ask your question. If you want to ask a question about your child, I would suggest going into the "Families" section and posting a thread there. You will get a lot more parents to read it if it's placed there.
Third: Is it just a resistant form of staph, or is it MRSA? For your reference, I have MRSA and staph in my lungs. The MRSA made my PFTs go to hell (44%), I went on my first round of IVs, and they popped right back up. We haven't seen any of the MRSA since 01, when I first cultured it. The staph is still always there, but it's hard to pinpoint <i>what</i> causes my lung issues, because in addition to the staph, I have 3 psuedomonases. Even with the MRSA, the staph, and the 3 pseudomonases, my lungs are in pretty good shape. I'm 23 years old and my PFTs have been around 70% for a few years now.
It's impossible to predict CF, under any circumstances. So I can't tell you your kid will be okay. If I was to bet on it, though, I'd say he will be. CFers live with all sorts of bacteria in their lungs and keep going anyway. And if treated fiercely, you may be able to get rid of the staph.
As for alcagines... no idea, sorry. Haha. <img src="i/expressions/face-icon-small-smile.gif" border="0">